auto ref is on the docket

[Daniel N via Digitalmars-d]

On Tuesday, 23 June 2015 at 01:07:17 UTC, Jonathan M Davis wrote:
> No, you can't guarantee that an auto ref parameter won't be 
> mutated, but auto ref clearly indicates that you intend to 
> accept both lvalues and rvalues, meaning that it would be 
> stupid to be writing the function with the idea that you would 
> be passing in an argument which would be mutated. ref on the 
> other hand clearly indicates the intention to mutate the 
> argument.
>
> - Jonathan M Davis

That is why, as a good API designer, you'd express that fact by 
adding const ontop of it, i.e. const ref.

Only for the few rare cases where you need to account for 
lazy-caching or similar mutating constructs, you'd be grateful to 
have the nice escape hatch, plain ref.

Daniel N